Question

Astronomical unit $(Au)$ is the average distance between the earth and sun approximately $1.5\times 10^{8}km$. The speed of light is about $3.0\times 10^{8}m/s$. The speed of light in astronomical unit per minute is

• A. 0.012 Au/min
• B. 0.12 Au/min
• C. 1.2 Au/min
• D. 12.0 Au/min

Answer 1

Answer: (B)

Average distance between the earth and sun, is approximately $1.5\times 10^{8}km$. Speed of light is $3.0\times 10^{8}m/s.$
$\therefore$ Speed of light in astronomical unit per minute
$=0.12Au/\min$